Dust mask



June 15, 1954 M. E. SWIN DELL DUST MASK Y Filed March 10, 1952 Melvin E. Swindell INVENTOR.

BY Maw 3M Patented June 15, 1954 UNITED STATES ?ATENT OFFICE 2 Claims.

The present invention relates to new and useful improvements in dust masks for use in industrial plants or under other conditions where the air to be breathed needs to be purified.

An important object of the present invention is to provide a rigid nose and mouth guard forming a holder for a replaceable filter attached to the guard in a manner to protect the face from direct contact with the guard to improve sanitation where the masks are dispensed to workmen for interchangeable use.

Another object is to provide a device of this character of simple and practical construction, which is efficient and reliable in use, relatively inexpensive to manufacture and otherwise well adapted for the purposes for which the same is intended.

Other objects and advantages reside in the details of construction and operation of the device as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a perspective view;

Figure 2 is a rear elevational view of the guard;

Figure 3 is a vertical sectional View taken on a line 3--3 of Figure 4;

Figure 4 is a horizontal sectional view taken on a line 4- of Figure 3 with the filter removed;

Figure 5 is an enlarged fragmentary sectional view showing one of the wire clips for holding the filter in position; and,

Figure 6 is a perspective view of the head strap.

Referring now to the accompanying drawings in detail, wherein for the purpose of illustration I have disclosed a preferred embodiment of my invention, the numeral 5 designates a rigid, substantially concavo-convex guard which may be constructed of composition rubber, plastic, metal or other suitable material, and adapted to cover the nose and mouth of the wearer. A relatively narrow vertically elongated hollow protuberance 6 projects forwardly from the guard to enclose the nose, and both the mouth and nose enclosing portions of the guard are formed with air openings 1. i

The entire edge of the guard is formed with an outwardly curved lip 8 and is shaped to the contour of the face of the person for close contact therewith at the bridge of the nose and at the chin, and an elastic or other suitable strap 9 is provided with hooks H! at its ends adapted to engage a pair of the openings 1 to attach the guard to the head of the person.

A cloth or other suitable flexible filter pad or sheet II is placed in the concaved side of the guard and is also of substantially concavo-convex shape to provide a rear air chamber l2 between the filter and the nose and mouth and a front air chamber I3 between the filter and the guard. The edges of the filter extend over the lip 8 and is clamped against the rear or outside of the lip by a plurality of resilient wire clips M secured to the guard by rivets or the like i5.

The filter not only provides a soft padding between the lip 8 of the guard and the face of the person, but also is replaceable and protects the face from contact with the guard to prevent the spreading of disease where different persons use the mask.

In View of the foregoing description taken in conjunction with the accompanying drawings it is believed that a clear understanding of the device will be quite apparent to those skilled in this art. A more detailed description is accordingly deemed unnecessary.

It is to be understood, however, that even though there is herein shown and described a preferred embodiment of the invention the same is susceptible to certain changes fully comprehended by the spirit of the invention as herein described and the scope of the appended claims.

Having described the invention, what is claimed as new is:

1. A dust mask comprising a rigid, substantially concavo-convex perforated nose and mouth guard, an outwardly extending lip at the edges of the guard, means attached to the guard adapted for holding the same over the nose and mouth of a person and with the lip held against the face of the person, a flexible filter member in the concavity of the guard folded over the lip, said filter member being of concavo-convex shape and forming in said guard a rear closed air chamber between said filter member and the nose and mouth of the person and a front air chamber in said guard between the filter member and the guard, and means carried by the guard clamping the filter member in folded position on the lip, said first named means including books engageable in selected perforations in the guard.

2. A dust mask comprising a rigid, substantially concavo-convex perforated nose and mouth guard, an outwardly extending lip at the edges of the guard, means attached to the guard adapted for holding the same over the nose and mouth of a person and with the lip held against the face of the person, a flexible filter member in the concavity of the guard folded over the lip, said filter member being of concavo-oonvex shape and forming in said guard a rear closed air chamber between said filter member and the nose and mouth of the person and a front air chamber in said guard between the filter member and the guard, and clips carried by the guard and removably clamping the filter member against the rear of the lip and in folded position thereon.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,579,449 Hubbell Apr. 6, 1926 1,837,591 Shindel Dec. 22, 1931 2,067,026 Schwartz Jan. 5, 1937 2,296,150 Dockson Sept. 15, 1942 

